Dental tool having shock absorbing mounting



July 3, 1956 A. D. WISEMAN DENTAL TOOL HAVING SHOCK ABSORBING MOUNTING Filed June 26, 1953 INVENTOR. 72 4004/11 0 VV/Sf/l MA/ ATTOIP/Vf/f DENTAL TOOL HAVDIG SHOCK ABSURBING RIOUNTING Adolph D. Wiseman, San Francisco, Calif. Application June 26, 1953, Serial No. 364,320 4 Claims. (Cl. 32-27) This invention relates to dental tools commonly used in connection with a dental handpiece, such as cutting, grinding, cleaning and polishing implements of all kinds such as may be held in a chuck on such handpiece and rotated by a dental engine, although some such tools may be stationarily mounted on a handpiece that is independent of the dental engine. The application is a continuation in part of application Serial No. 129,758, filed November 28, 1949 now patent No. 2,656,559.

Heretofore most tools of the above character have been held in the chuck of the handpiece by a quick releasable latch or detent, or by other quick detachable means. Each such tool has heretofore had a metal shank piece adapted to be engaged by the metal chuck of the handpiece. In very few instances do the tools rotate on the central axis of the shank piece, but instead, their as comes within the tolerances permitted turer. Irrespective of the reason for the tools rotating eccentrically, it is obvious that such occurrence results in materially increasing the discomfiture of the patient when the tool is used on a sensitive tooth. And even where absolute precision is obtained, the vibration from gears, and other hard parts associated with the gears and with the drive to the tool is transmitted directly to the tool and from thence to the tooth of a patient.

it has been discovered that a shock absorber positioned between the tool and handpiece will virtually eliminate the objectionable transmission of shock and vibration to the tooth, thereby reducing the discomfiture of the patient by a very substantial amount.

One of the objects of this invention is the provision of simple, economical structure whereby a shock and vibration absorber is incorporated into the connection or mounting of the dental tool without requiring a special shank piece for securing the tool to the handpiece.

Another object of the invention is the provision of improved structure for holding a dental brush, cutting, grinding, cleaning, polishing and other dental tools in or to a conventional handpiece with maximum protection for the teeth and mouth of the patient from injury due to engagement of metal parts with the teeth.

A still further object is the provision of a dental tool that overcomes the objections to metal socket or base members heretofore associated with dental tools, and at the same time provides means for quickly and securely fastening a metal tool to a shank piece that in turn is adapted to be held by a dental handpiece.

Other objects and advantages will appear in the description and in the drawings.

in the drawings, Fig. 1 is a fragmentary side elevational view of a portion of a dental handpiece having a dental tool secured thereto, which tool embodies the present invention.

Fig. 2 is a sectional view through the dental tool that is secured to the handpiece of Fig. 1.

by the manufacof the conventional handpiece 1.

Fig. 3 is a sectional view through a dental tool that is similar to that shown in Fig. 2. The tool of Fig. 3 shows a slightly different cutter and slightly dilferent structure for holding the tool and rubber mounting onto the shank piece.

Fig. 4 is a sectional view similar to that of Fig. 2 showing a still further modification and showing a grinder or polisher.

Fig. 5 is a sectional view similar but showing a brush and structure.

Fig. 6 is a sectional view showing a burr and a slightly for the tool.

Fig. 7 is a sectional view similar to that .of Fig. 6 showing a further modification of theinvention.

In practice the usual dental handpiece may be straight to that of vFig. 2, a slightly different mounting similar to that of Fig. 5 different form of mounting or motor through a driven shaft 2. The chuck is not shown in detail inasmuch quite old, and various tools for use with the handpiece, such .as burrs, polishers, cutters, grinders, brushes, etc. are provided with long or short shanks for securernent in the chuck of the straight or angle handpiece, as the case may be.

In my United States Patent No. 2,017,881 of October 22, 1935, a shank piece of a dental tool is shown that is suitable for certain forms of the present invention and which incorporates features that are desirable for use in other forms.

A preferred form of the present invention is shown in detail in Fig. 2 in which a shank piece 5 is provided, and which shank piece is adapted to be secured in the chuck This shank piece is provided at one end with a circular exteriorly threaded fit into a complementarily formed socket or recess 9 formed in the base memsuch as the burr, polisher, etc.

This holder 11 is preferably formed of relatively soft, flexible rubber preferably of mouth of the recess.

The implement 17, indicated has a shank 18 that is secured sleeve that is at the outer end of recess 12 is slightly below the outer edge of the recess.

From the foregoing, it will be seen that the sides of recess 12 generally form a skirt that fully encloses the sleeve 19 that in turn holds the shank of the implement that is to be used.

In many instances, where the shank 18 is relatively short and where too much side pressure is not applied to the burr, cutter or other implement, the foregoing structure is ample for holding the holder 11 onto the shank piece that carries the bulbous projection '7, and Fig. 6 shows such structure insofar as the holder itself is concerned.

However, it is desirable that a flange be provided on the head 6, or in some way associated therewith for extending over the rotary chuck of the handpiece. Such flange is provided in Fig. 2 in the form of a collar 28 that is adapted to slip over the holder 11 and over the base portion 18 of the latter. This collar has an enlarged diameter end portion 23 that is interiorly threaded to engage the threads on head 6, and the other end 22 is slightly less in diameter so as to apply slight radially inwardly compressive pressure to the base member so as to insure against said holder slipping off the bulbous projection 7 if substantial lateral pressure is applied to the implement 17. A shoulder 24 at the junctures between end portions 23, 22 of the collar will seat against the head 6 at its edges to limit the movement of the collar axially of the head when the collar is in holding position as seen in Fig. 2.

It is preferable that the end portion 22 of the collar extend to a point slightly past the maximum diameter of the bulbous projection 7.

By this means the portion 23 of the collar will provide the flange that would otherwise be rigid with the shank piece, as indicated at 25 in Fig. 6 where no collar is used. Obviously the end portion 23 may be only threaded at the part that is in engagement with the head 6 if desired.

By the foregoing structure it will be seen that any objectionable eccentricity in the chuck or any objectionable vibration transmitted to the shank piece will be substantially absorbed by the body 11 which includes web 13 and will not be transmitted to the implement 17 that is adapted to engage the teeth. At least the amount that will be transmitted will be greatly reduced, with the result that many operations heretofore quite painful to the patient will either be painless or nearly so.

Inasmuch as the shank pieces of Figs. 3, 5, 6 and 7 are subsantially identical, they will be given the same numbers, and likewise the same numbers will apply to sockets in the rubber holders of Figs. 3, 5, 6 and 7 since these are all alike.

In Fig. 3 a slightly different means is used for giving additional security to the holding of the rubber or resilient implement holder to the shank piece.

In Fig. 3, the shank piece 26 and head 27 have flanges 25 thereon as already described for Fig. 6. The shank pieces 26 are the same. A bulbous projection 29 is secured to head 27 and the body 31 in Fig. 3 is formed with a socket 33 for receiving said projection 29, while a web 34 forms the closed end of the recess or socket 33, all the same as described for Fig. 2.

Opposite the recess 33 in Fig. 3, the holder 31 is formed with a cylindrical outwardly opening recess 35 that is coaxial with recess 33.

The implement 36, which may be for any desired operation, has a shank 30 that is secured in a sleeve 37. This sleeve 37 is formed with a radially outwardly extending flange 38 at its end remote from the implement 36, and an axially directed flange 39 is provided along the outer edge of said flange 38.

The sleeve 37 fits in recess 35 and flanges 33, 39 fit in complementarily formed recesses in the holder 31 with the flange 39 extending axially past the projection 29 on the shank piece, but spaced outwardly of said projection so as to leave a cushion of rubber between the flange 39 and the projection 29.

By this structure, the projection is securely held in the recess of the holder 31 in the event an excess of side pressure is applied to the implement 36.

The similarity between this structure and that of Fig. 2 is clear, since both show a band or collar around the projection 7 (Fig. 2) or projection 29 (Fig. 3). In Fig. 2, the collar is secured to the shank piece while in Fig. 3, it is secured to the sleeve that is rigid with the implement. Fig. 2 is preferable in one respect since the removal of the rubber holder 11 is easier after the collar is removed, and also the holder can more easily be secured to the shank piece, but the structure of Fig. 3 has the advantage of eliminating a loose or separable collar.

The form of invention in Fig. 2 provides a slightly more secure connection between the holder 11 and the shank piece.

In Fig. 4, a still different form is shown, in which the shank piece 4% has a head 41 which, in turn, has a bulbous projection 42 and a flange 43. These elements are identical with correspondingly described elements in Figs. 3 and 6, except that the projection 42 is formed with a central opening or hole 44. The holder 45 of rubber is the same as the holder of Fig. 6 except that the web 46 is provided with an opening for passage of an extension 47 of the shank 48 of the implement 49.

This shank 48 is secured in a sleeve 50 that has flanges 51, 52 at its upper and lower ends and which sleeve is fitted in a complementarity formed recess in holder 45.

The opening or hole 44 is substantially larger in diameter than the diameter of the projecting end 47 of shank 43, so that the body 45 will be flexed to one side or the other upon side pressure on implement 49 without the extension 47 touching the sides of the opening 44. However, if such a degree of side pressure is applied as would otherwise be likely to pull the body 45 off the projection 42, the extension 47 will engage the inner side of the opening 44 to prevent such separation. This structure is not as desirable as that of Figs. 2 and 3 should the operator be one who uses excessive lateral pressure on the implement, but the shock absorbing features are fully preserved up to the time the shank contacts the side of recess or opening 44, and even then some of the benefits are retained.

In Fig. 5, a brush 55 consisting of a body of bristles 56 is held at one of its ends in a sleeve 57 that in turn has a radially outwardly extending flange 53 at its end remote from the exposed bristles.

The rubber holder 59 is identical with the holders of Figs. 2, 6 except that the outer end of recess 60 for the sleeve 57 need not be recessed inasmuch as no flange is provided on that end of the sleeve 57. The flange 58 that is on the sleeve 57 extends into a complementarily formed recess at the inner end of recess 60, and a web 61 is between the projection 29 of the shank piece and the sleeve 57.

In Fig. 7 of the drawings, the structure is the same as that of Fig. 6 insofar as the bulbous projection 29, head 27, flange 25 and shank piece 26 are concerned.

The rubber holder 70 is identical with the holder 71 shown in Fig. 6, except that it has a skirt 72 that extends over the flange 25 and that frictionally grips the flange 25. The spool like sleeve 73 is secured in the recess that opens oppositely outwardly of the recess in which projection 29 is held, and any desired implement 74 may be rigid with said sleeve.

In many respects, does not require any shank piece.

The durorneter hardness of said holder 70 is preferably about although it may be from about 50 to 80.

In each instance, the assembly including the shank piece and the implement, whether the latter is a brush, burr, grindstone, etc., may generally be called a dental this is the preferred form since it separable parts to hold it to the tool, since the assembly is handled as a unit for attachment and detachment to the handpiece.

While the rubber or resilient holders are usually made separable from the shank piece, they could be cemented thereto by any suitable sterilizing temperatures, but in such a structure the expense or cost would be increased since the operator would have to dispose of the shank piece whenever the holder or implement became worn, although the shank piece was still in perfect condition.

Also, if desired, the various sleeves and implements may be cemented to the holders or they may be replaceable. The provision of the web between the sleeve holding recess and the recess for the head of the shank piece contributes materially to the frictional resistance to tuming of the holder relative to both the sleeve and to the shank piece.

It is the intention of the claims appended hereto to cover all changes and modifications of the examples of the invention herein chosen for the purposes of the disclosure, Which do not constitute departures from the spirit and scope of the invention.

I claim:

1. In combination with an elongated rigid shank piece adapted to be secured in the rotatable chuck of a dental hand piece, a tooth engaging implement having an elongated rigid shank, a holder securing said shank piece and the shank on said implement together in coaxial alignment and with said shank piece and shank projecting from opposite ends thereof for rotation of said implement and said shank piece together as a unit upon rotation of said shank piece, said holder being of resilient, flexible, relatively soft, shock absorbing material free from exterior restraint to flexing of the end portion from which said implement projects under a lateral application of force against said implement, and a body of the material of said holder disposed between said shank piece and said shank on said implement for absorbing vibration from said implement directed axially along its shank and for spacing the latter from said shank piece.

2. In combination with an elongated rigid shank piece adapted to be secured in the rotatable chuck of a dental hand piece, a tooth engaging implement having an elongated rigid shank, a holder securing said shank piece and the shank on said implement together in coaxial alignment and with said shank piece and shank projection from opposite ends thereof for rotation of said implement and said shank piece together as a unit upon rotation of said shank piece, said holder being of resilient, flexible, relatively soft, shock absorbing material free from exterior restraint to flexing of the end portion from which said implement projects under a lateral application of force against said implement, and a body of the material of said holder disposed between said shank piece and said shank on said implement for absorbing vibration from said implement directed axially along its shank and for spacing the latter from said shank piece, a sleeve enclosed by said holder in which the shank of said implement is held and a member on said shank piece rigid therewith at the end of said shank piece that is adjacent to the shank of said implement enclosed by said holder, said sleeve and said member being spaced apart by said body of the material of said holder.

3. In combination with an elongated rigid shank piece adapted to be secured in the rotatable chuck of a dental hand piece, a tooth engaging implement having an elongated rigid shank, a holder securing said shank piece and the shank on said implement together in coaxial alignand said member being spaced apart by said body of the material of said holder, said sleeve and said member each having a flange extending radially outwardly relative to the axis of said shank piece and said shank at opposite ends of said holder and over material of said holder at said ends.

4. In combination with an elongated rigid shank piece adapted to be secured in the rotatable chuck of a dental hand piece, a tooth engaging implement having an elon- References Cited in the file of this patent UNITED STATES PATENTS 926,303 Thompson June 29, 1909 1,889,494 Priest Nov. 29, 1932 1,982,336 Wiseman Nov. 27, 1934 1,993,763 Touchstone Mar. 12, 1935 2,300,828 Goldenberg Nov. 3, 1942 2,306,264 Hart Dec. 22, 1942 2,656,559 Wiseman Oct. 27, 1953 FOREIGN PATENTS 540,158 Germany Dec. 8, 1931 926,303 Germany June 29, 1909 

